The London police force's failure to root out a long-time serial rapist from its staff reflected "cultural issues" within the force, Mayor of London Sadiq Khan said on Tuesday.
David Carrick, a former Metropolitan Police Force officer, was unmasked as one of Britain's most prolific sex offenders.
The 48-year-old was found to have committed gross misconduct after admitting 49 criminal charges including 24 counts of rape against 12 women over an 18-year period.
Speaking at a housing development in east London's Docklands, Mr Khan told the PA news agency: "Londoners will be shocked and appalled that someone who has been a serving police officer for almost 20 years was a prolific sexual offender."
"But also what's unacceptable is there were various opportunities where the chance to get rid of him and get justice were missed," the mayor added.
At a disciplinary hearing in Earl's Court on Tuesday, Assistant Commissioner Louisa Rolfe said: "This is a sickening and horrific case with far-reaching consequences for policing."
Carrick faced complaints about his behaviour before he joined the force in 2001, then again as a probationer in 2002 and several times throughout his policing career until 2021.
Khan said Metropolitan Police Commissioner Sir Mark Rowley's senior team "is looking back at any allegation from the last 10 years made against police officers and other police staff to see if there are other cases where opportunities were missed.
"I think Londoners deserve nothing less."
Rowley said weak policies and decisions meant Carrick was able to stay in the force for 20 years, despite repeated complaints being made against him.
Rowley told BBC Breakfast: "We've let London down - he's been a police officer for 20 years.
"Through a combination of weak policies and weak decisions, over those 20 years we missed opportunities when he joined and subsequently, as behaviour cameto the fore that we should have removed him from policing.
"Whether it would have affected him being a sex offender I don't know, but he shouldn't have been doing it as a police officer."
